Friday, September 30, 2011

Evolutionary Psychology Crap in New Scientist

What can evolution tell us about domestic violence? Two researchers in the US suggest such violence has ancient origins and that establishing evolution's role could help to better identify those at risk. Others argue that the research makes simplistic assumptions, and warn that some people will interpret the research as an excuse for violence.

Each year more than 500,000 women in the US alone report to the police violent attacks by current or former male partners. There is a reason why domestic violence is so widespread, says David Buss, an evolutionary biologist at the University of Texas in Austin: it carries a selective advantage, tied with reproductive success. In other words, men who are violent are trying to make sure that their partner has his child and not another man's.

Let's think about this for a minute.

In order for violence against women to have a selective advantage there has to be an important genetic component. Let's imagine a time back in hunter-gather days when there were two groups of men who differed in their violence-against-women alleles. One group was kind and considerate toward their female companions. They treated them with respect. The other group treated women as property and often beat them in order to prevent imagined infidelity. Somehow the violent group managed to mate more frequently and/or have more children than the kind group so the allele for kindness and respect was eliminated from the population.

Lots of things had to happen in order for this scenario to play out as the evolutionary psychologists imagine. For example, women had to prefer to have children with men who would beat them. (Or maybe they were forced to mate with the violent men.). Furthermore, there had to be no consequences for the men who beat their mates. The other members of the group had to tolerate that behavior even if they found it repulsive.

If the scenario is correct then most men—including you and I—have to carry the violence-against-women allele since it was selected in the past. This seems very strange since most men don't beat their wives.1 I guess we have learned to suppress the genetic urge. But why would we do that if it's a selective advantage to engage in domestic violence?

There's also something seriously wrong with men who engage in domestic violence. They are assholes who deserve very little sympathy from the rest of society. I suspect they got no sympathy in ancient hunter-gather societies either. There is no gene that makes you act like an asshole. That's all due to nurture and it can be changed if we put our minds to it.

1. At least I think this is true. When was the last time you beat your wife or girlfriend?

54 comments
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I suspect they got no sympathy in ancient hunter-gather societies either.

As nice as it might be to believe that was true, there exists a subculture of macho misogyny in which being tough with one's wom[a|e]n is considered a virtue. It's far from universal, but it's not hard to imagine it existing in ancient society as much as today.

I think you're being WAAAYY to optimistic on it being 'shunned' in ancient times, or any times except right now in parts of the west, and even then only when blaringly obvious.Of course, that still doesn't mean it has a genetic basis and a selective advantage anyway. Seems like evolutionary psychology should be, you know, investigating that part.

"There is no gene that makes you act like an asshole. That's all due to nurture and it can be changed if we put our minds to it."

There certainly seems to be evidence that is generally true. But you are also letting your indignation get ahead of you. You don't actually know if there is a gene that makes some people act like assholes.

Also, how have the rates of spousal abuse changed over the years and across cultures? I would bet that it has been declining sharply over the years and that today there will be large variations across cultures. I'd bet that some cultures (such as ones that still practice honor killings) tend to have much higher levels of spousal abuse than western cultures which do not.

In other words, the variation has a strong cultural component which they don't seem to have acknowledged let alone tried to quantify.

I've always been weary of Evolutionary Psychology explanations of behaviours. Particularly complex ones. Is it all speculative?

I'm aware that there has been some loose connections in behaviours that have been suggested. There have been studies that claim to have shown correlations between monozygotic twins and homosexuality. And also, I've heard on line that the female siblings of homosexuals tend to be more fertile.

I'm basing this mostly on heresy here; but do you think an explanation of the sort outlined above could ever be true?

As nice as it might be to believe that was true, there exists a subculture of macho misogyny in which being tough with one's wom[a|e]n is considered a virtue. It's far from universal, but it's not hard to imagine it existing in ancient society as much as today.

Violence against women is not condoned in most modern societies. As far as I know it wasn't tolerated in most ancient societies (Roman, Chinese, Japanese, Greek, Hindu, Jewish etc.). I see no scientific reason to imagine that it was condoned in primitive societies either.

Is there any evidence that modern hunter-gatherer societies allow men to beat up their wives?

I don't understand why modern men find it so easy to imagine that our ancestors treated women so badly. And why would women, collectively, put up with it any more than they do today? Were they too stupid to realize that being constantly beaten was not healthy?

You don't actually know if there is a gene that makes some people act like assholes.

If you don't actually know whether a given behavior gene (allele) exists then isn't it rather silly to build an entire field of study (evolutionary psychology) based on unwarranted speculation?

It's actually worse than speculation. We're beginning to know enough about our 20,000 genes to be able to say with some certainty that there aren't single genes resonsible for each type of human behavior that's been attributed to genetics. There may be suites of genes that influence behavior—such as making a man or woman more prone to violent behavior—but it's very unlikely that there are combinations of alleles that specifically make men behave more violently toward their wives and not toward anyone else.

I would also suggest there is not a clear model of this behavior in other species, especially apes. Male on male violence is much more common.

But that's exactly what evolutionary psychology requires. Most of their arguments rely on selection for specific behavior in primitive humans. That means that the behavior (beating up on women) was NOT present in our ancient ancestors.

If all the great apes exhibited this violence-against-women behavior then there would be no reason to speculate on how it became fixed in our hunter-gatherer ancestors.

As far as I know it wasn't tolerated in most ancient societies (Roman, Chinese, Japanese, Greek, Hindu, Jewish etc.). I see no scientific reason to imagine that it was condoned in primitive societies either.

There have been several books and studies out recently showing that violence in general has declined significantly throughout our history. Is it so unreasonable to imagine that rates of domestic violence have declined as well?

I don't know of anyone that has tried to compile stats since this is so hidden and underreported even today. However it doesn't take much to look at some actions which were considered acceptable in the past and are abhorrent today to infer that domestic violence used to be far worse than it is today.

For instance, according to this, in 750BC men could beat their wives with "a rod or switch as long as its circumference is no greater than the girth of the base of the man's right thumb, hence 'The Rule of Thumb.' The tradition of these laws is perpetuated in English Common Law and throughout most of Europe."

In the middle ages, "In Europe, squires and noblemen beat their wives as regularly as they beat their serfs; the peasants faithfully followed their lords' example. The Church sanctions the subjection of women. Priests advise abused wives to win their husbands' good will through increased devotion and obedience."

In the 1500s, the law refuses to recognize raping your wife (as she has implicitly consented with the marriage).

As late as 1824 in the US 'A decision by the Mississippi Supreme Court in Bradley v. State 2 Miss. (Walker) 156 (1824), allows a husband to administer only "moderate chastisement in cases of emergency. . ."'

In the 1880s a court in the US decide that husbands can freely beat their wives "unless the battery is so great as to result in permanent injury, endanger life and limb". In England at this time courts rule that a woman whose husband beat her so badly as to regularly endanger her life was able to separate from him, but not divorce.

Even though these seem shocking to me, they're still marks of improvement over time. Things really accelerated in the 20th century. At the turn of the Century, the British passed laws declaring that "wives can no longer be kept under lock and key, life threatening beatings are considered grounds for divorce, and wives and daughters can not longer be sold into prostitution."

In 1924, France overturned the Napoleonic code which declared "Women, like walnut trees, should be beaten every day".

Finally in 1945 California makes it a felony for a husband to beat his wife or children and laws (like murder) which discriminate based on gender are unconstitutional.

If any of this is even remotely accurate, I think it shows that spousal abuse was probably more common and certainly far more severe on average than what happens today. It looks like there has been a decline in domestic violence.

Does this necessarily mean that it was so prevalent in our deep evolutionary past that it could been a selective force? I doubt it. In fact, as I tried to say earlier I think this shows that domestic violence is predominantly a cultural phenomenon.

So is there an advantage to females selecting for males that would beat them up?

Very well can be. If beating up a mate is a side effect of the male being stronger and more aggressive. And if the stronger and more aggressive male is more likely to win competition for females, survive and reproduce then it is = fitness advantage.

Of course this is pure speculation and the EP story told that Larry cites does not extend beyond the usual just-so. EP is a field where main occupation seems to be coming up with plausible-sounding speculations. They really need to tone down on their completely unsubstantiated tales.

The article and the response are both assuming behavioral effects that are far too specific. Might there be (or have been) an advantage to aggressive behavior or having less control over one's temper? Maybe. (I remember a friend of mine, who so far as I know was not aggressive toward women and didn't have a problem with physical violence, saying to me that in a negotiation your opposite number should be 99% sure, but not 100%, that you wouldn't come across the desk and smack him.)

I worked with battered women and an organization that assisted them, and the statistics on the incidence of domestic violence are eyebrow-raising to say the least. In the USA it was responsible for 25% of homicides and occurred in 10% of households last time I looked at statistics. I don't believe we are quite as civilized as we like to think.

One last point re "assholes:" When working with abusers, including child abusers, one can make no headway at all with that attitude. One has to relate to the abuser as a human being, and accord him/her (though not the behavior) proper respect to have any chance of being listened to and affecting behavior in a positive way. And of course, telling an abuser he/she must treat others with respect while not treating him/her with respect is utterly hypocritical and will quite properly fatally undercut the message one is trying to deliver.

The idea is not that I was calling anyone else hypocritical. The idea is that if you are evidently not practicing what you preach when talking to someone, it makes it far more difficult, if not impossible, to be convincing. Why should they do what you say, if *you* don't do what you say?

I'm becoming very tired of hearing of 'evolutionary psychology'. Psychology is a science and discipline that is still very much in its infancy, and already it's trying to make its mark in other fields. Back off until you are ready, and you aren't anywhere near it yet.

When working with abusers, including child abusers, one can make no headway at all with that attitude. One has to relate to the abuser as a human being, and accord him/her (though not the behavior) proper respect to have any chance of being listened to and affecting behavior in a positive way

The best way to change society is to make certain behaviors unacceptable. I'm not talking about treating an individual spousal abuser when I use the term "asshole" to describe such a class of people.

What I'm trying to do is reinforce the idea that such behavior is totally unacceptable in modern society and it's up to all of us to stop tolerating it. In this context, I'm not interested in treating abusers—I'm interested in preventing the behavior in the first place.

Part of this goal is to show that violence in not in our genes. We men do not carry alleles that make us beat up women because such alleles were advantageous in the past.

The best way to change society is to make certain behaviors unacceptable. I'm not talking about treating an individual spousal abuser when I use the term "asshole" to describe such a class of people.

What I'm trying to do is reinforce the idea that such behavior is totally unacceptable in modern society and it's up to all of us to stop tolerating it. In this context, I'm not interested in treating abusers—I'm interested in preventing the behavior in the first place.

I think domestic violence, violence against the helpless, violence against those at a disadvantage (size, strength, etc.), unprovoked violence, etc., are nearly universally considered unacceptable at a social/cultural level in the USA, for example. Yet the statistics show a sickening prevalence. So while I agree that it is rightfully considered unacceptable and wish you were correct that the prevailing cultural attitude is the best way to minimize these acts, I don't think the facts bear this out.

One thing to bear in mind is that just being brought up in a household in which violence is prevalent has a terrible impact on children exposed to it. I will never forget seeing a 5-year-old girl at a shelter hug a plush stuffed frog with a smile on her face, then watching her face change into a mask of rage as she pushed her thumbs into the frog's neck and began choking it and beating its head on the ground. I assume that's how she was accustomed to seeing her father express his 'love' for her mother and/or her. I have tremendous concerns about the efficacy of societal disapproval in the face of such early 'child training.' It may take getting through to individual abusers and abuse victims (helping to convince them that they don't deserve what they're getting, and that they can and should get out) to break a cycle so deeply inculcated at such an early stage.

Part of this goal is to show that violence in not in our genes. We men do not carry alleles that make us beat up women because such alleles were advantageous in the past.

As I said upthread, perhaps there is a plausible argument to be made in favor of selection of alleles that promote more aggressiveness or less personal control. But regardless of whether that's so or not, obviously most people are able to behave non-violently and it is eminently reasonable IMO to expect non-violent behavior from everyone.

So while I agree that it is rightfully considered unacceptable and wish you were correct that the prevailing cultural attitude is the best way to minimize these acts, I don't think the facts bear this out.

So you don't think that changing society is the way to change society?

What's the alternative? How do you propose to eliminate violence in our society unless you can convince the people that it's not an acceptable way to behave?

Do you think you can achieve the goal by other means or are you saying that it's impossible?

What's the alternative? How do you propose to eliminate violence in our society unless you can convince the people that it's not an acceptable way to behave?

I think you may be at too general a level. I doubt whether you will find even a very small percentage of people in, for example, the USA willing to say they condone domestic violence, or that it should be tolerated. Nevertheless it's practiced (by people who sometimes suffer such deep shame and regret afterward that they commit suicide). So convincing society it's wrong and shouldn't be tolerated has already largely been done, from my point of view.

Do you disagree? Do you think there are a significant percentage of people in the USA in favor of domestic violence?

I believe convincing society that domestic violence is wrong is necessary but not sufficient to try to resolve (or at least ameliorate) the problem.

Do you think you can achieve the goal by other means or are you saying that it's impossible?

I hope it is not impossible to make significant inroads. But I think because of the way this behavior occurs and is propagated through generations (children of abusive relationships are more likely to be abusers or to become victims of abusive relationships), intensive individual work, beyond any general societal condemnation, is necessary to help adults understand that the types of behaviors they've been steeped in since they were children are not inevitable.

Sort of off-topic, but I really wish that stupid rule of thumb myth would go away. The idea that it orginates from a man being able to beat his wife with something thinner than his thumb is a modern invention for the meaning of the phrase. http://www.phrases.org.uk/meanings/rule-of-thumb.html

I think you may be at too general a level. I doubt whether you will find even a very small percentage of people in, for example, the USA willing to say they condone domestic violence, or that it should be tolerated. Nevertheless it's practiced (by people who sometimes suffer such deep shame and regret afterward that they commit suicide). So convincing society it's wrong and shouldn't be tolerated has already largely been done, from my point of view.

There's a difference between "condone" and "tolerate." There was a time in the 1950s and 1960s when most Americans did not "condone" racial discrimination but, nevertheless, it was "tolerated" in large parts of the country.

Then people woke up and realized that racial discrimination was always wrong and it should never be tolerated in a civilized society. Within a few years membership in the Ku Klux Klan went from being a badge of honor to an embarrassment. Today you won't find very many people who openly admit to being a member of that odious organization.

Spousal abuse is almost universally condemned. However, friends, neighbors, and relatives will frequently ignore spousal abuse when they know it's happening. They think that it's none of their business to interfere in the private lives of their friends or relatives.

That's what I mean by "tolerance" and that's got to change. Violence in society is everyone's business.

[F]riends, neighbors, and relatives will frequently ignore spousal abuse when they know it's happening. They think that it's none of their business to interfere in the private lives of their friends or relatives.

That's what I mean by "tolerance" and that's got to change. Violence in society is everyone's business.

This is a disappointing and unscientific post. Instead of carefully reading the original paper and criticizing specific parts of it, Mr. Moran chose to bash a New Scientist summary of it. It's shoddy analysis to draw conclusions about a primary reference based on a secondary source. I expected better from someone who calls himself a scientist.

This is a disappointing and unscientific post. Instead of carefully reading the original paper and criticizing specific parts of it, Mr. Moran chose to bash a New Scientist summary of it. It's shoddy analysis to draw conclusions about a primary reference based on a secondary source. I expected better from someone who calls himself a scientist.

This is an article that criticizes the popular press and how they report on what's in the literature.

Of course I am also implicitly criticizing the actual study since I have a very low opinion of evolutionary psychology.

I've read the paper. If you think it's any better than the summary in New Scientist then feel free to defend evolutionary psychology as best you can. Please start by pointing to the discussion in the paper about the genetic basis of behavior and why the authors are assuming natural selection of specific alleles.

Next you can address the issue of how and when violence aganst women was selected in populations of our ancestors. I'm sure that must be in the paper somewhere although I seem to have missed it it my first reading.

Excellent post Larry. This shows just about the very worst of Evolutionary Psychology. Not least of the problems I have is the idea that violence has evolved in such a way as to be person-specific i.e. "There's a gene for" violence against partners in particular. Is violence against a Post Office worker specifically genetically encoded too? How about violence against the Police?

At no point in the paper that I could see did the authors say that a single gene or allele was responsible. I think they just assume that there is a genetic component to behaviour. I'd be surprised if that wasn't true. The question is simply how much and which specific behaviour? Complex behaviour is likely to be a complex product of both genetic and environmental background - nature AND nurture. Most adaptive traits are actually like this, so again the question is how much? The authors do not claim to answer this.

They say: "Our co-evolutionary theory of intimate partner violence clearly offers just a preliminary roadmap and makes no pretense to completeness."

I think that attacking a single-gene/adaptive allele is attacking a straw man. Is it really so unlikely that certain genetically encoded traits could affect the tendency of an individual to be violent in certain circumstances? Is it really unlikely that violence and irrational behaviour is under some level of hormonal control? Is it really unlikely that hormones are not under some level of genetic control?

Finally, do we really need to have the genes/alleles identified before we can begin to speculate about underlying genetic influences and make hypotheses to test based on this? It is not just evolutionary psychology that makes these assumptions when it is useful. If the authors indicated that they thought the job was done, I think you'd have a point. But they didn't.

@Larry, Are you implying that they think there is a gene (or genes) for wife-beating, in the same way that there is a gene for enzyme X? I am pretty sure that this is not what is being suggested. Behaviour is a complex trait, governed by many complex genetic and environmental factors. If there IS a genetic component, however, it MUST be subject to selection and drift, as all genetics are. The genes responsible for this behaviour - IF they exist at all (and I am not saying that they do, only that they could) - are likely to be multiple loci that affect multiple traits. The net result of certain combinations of alleles at certain loci is an increased tendency for certain behaviour. IF this is advantageous, these alleles with undergo selection and increase in frequency, will they not? (Unless, which is also possible, these advantages are countered by pleiotropic negative phenotypes (behavioural or otherwise).)

I feel that the rest of your questions highlight further misunderstanding of the scenario. It is possible that some - but not all - of these genetic variants have become fixed in the population but their phenotypic outcome is dependent on the genetic background in which they sit and the environment in which the individual develops and lives. It is not necessary for them to be fixed, just maintained at high frequency in the population. True "fixation" is largely a myth. There is no "Human Genome" - variability is rife and we each have a unique genome. The recognition of this fact is opening up great opportunities in personalised medicine and I don't see why psychology and psychiatry should be any different in principle. There are many traits that have presumably been under selection - such as looks, atheletic ability, intelligence and hand-eye coordination - but are not universally found in all humans; we are not all beautiful, underwear-model Einsteins who could play professional sport if only we tried a little harder. I do not see why a complex behavioural trait should be any different.

I personally don't think that all humans are programmed to beat up their spouses if suspected of infidelity but I don't feel that it makes a difference to whether it could be genetically influenced and under selection. Even in the extreme single gene/allele scenario, there need not be a one-to-one genotype/phenotype mapping - it's called "incomplete penetrance".

It seems perfectly reasonable to me that aggression, jealousy, paranoia and response to stress are all continuums (continua?) that are in part influenced by the underlying genetics that builds the underlying brain. You admit that "it's certain that some violent and irrational behavior is due to specific alleles segregating in the population." Why is it so hard to imagine a perfect storm of aggression, jealousy and paranoia that triggers a violent response to suspected infidelity? I am not saying that I think this is the case but I certainly cannot rule it out and I do not see how you can, either. Why do you rule it out? Or is it just the advantageous aspect that you disagree with? (I'm not sure that I agree with this aspect either but this is not a nail in the coffin of evolutionary psychology any more than ill-advised adaptionism invalidates all evolutionary biology.)

Beyond incomplete penetrance at the level of building a potential spouse-abusing brain, I think there are many other reasons why we are not all spouse-beaters, even if it has been selected in the past. Firstly, the trigger scenario(s) probably don't happen for many/most people. (One of the potential uses that I personally can see for evolutionary psychology is predicting/identifying potential trigger scenarios.) Secondly, we do not all exhibit aggression in the same way. In the modern world, other forms of aggression - psychological abuse - might be more common and/or effective. Are there that many men or women that would not meet suspected infidelity with any form of aggression? .

The final thing I would say is that we are not slaves to our urges. Some people probably have the urge to strike a partner but manage to resist it. Some people don't. As you say, the latter are assholes. A genetically programmed asshole is still an asshole. Another possible use of evolutionary psychology might be to help such people identify "risk factors" to particular behaviours and avoid/deal with the relevant scenarios.

"You really don't get the objections to evolutionary psychology, do you?"

To this particular paper or the entire discipline? I hope you do not mean the latter. I get twitchy when someone starts writing off an entire discipline/field because it usually mean they have misunderstood it. (The only people I usually see doing it are Creationists.)

These are not a handful of kooks self-publishing on the internet and in obscure journals. These are intelligent people, working for respected insititutions of learning and publishing in peer-reviewed scientific literature. Either way, the answer is "No". I am sure that there is a lot of crap evolutionary psychology done - there's a lot of useless regular psychology done. (And ecology, and biochemistry, and evolutionary biology, and bioinformatics, and any other field you care to mention.) There may even be flaws in the paper covered by New Scientist but, if there are, you have not yet drawn attention to any of them as far as I can see.

I am open to being shown otherwise but, to me, the only real problem here is the poor coverage and over-hyping of pretty preliminary findings by New Scientist. This is nothing new, in my experience. New Scientist is science entertainment more than science education.

I feel that the rest of your questions highlight further misunderstanding of the scenario.

You're referring to my postulated "misunderstanding" of the possible complexity of specific behaviors such as wife-beating-under-specific-circumstances.

There is no misunderstanding. I know perfectly well that if such specific behaviors have a genetic component them it's likely to involve several loci.

The more loci that are involved the more difficult it is to make the just-so story fit with reality. That's why it's easier to talk about just one allele to highlight the problems with the just-so story.

If the evolutionary psychologists can't defend their story when there's only one or two alleles involved then they don't rescue themselves by quibbling about more alleles.

It's a red herring.

It is possible that some - but not all - of these genetic variants have become fixed in the population but their phenotypic outcome is dependent on the genetic background in which they sit and the environment in which the individual develops and lives.

That's quite possible although most of the just-so stories imply fixation. If the penetrence of the alleles is low then it becomes more difficult to postulate a selective advantage.

You can't have it both ways. Either there's a strong selective advantage and high penetrance leading to a selective sweep in our ancestors, or the selective advantage is not strong and/or the penetrance is weak and the alleles did not become fixed. You need a different just-so story to explain the second scenario.

If the alleles have not become fixed in the population then it should be possible to find men who don't have the wife-beating-under-special-circumstances allele. Do they have fewer offspring, on average, than the wife-beaters?

I bet there are dozens of evolutionary psychologists writing grants to carry out these studies. :-)

It is not necessary for them to be fixed, just maintained at high frequency in the population. True "fixation" is largely a myth.

Nonsense. By comparing the typical human and typical chimp genomes we've discovered more than a million examples of fixation.

There is no "Human Genome" - variability is rife and we each have a unique genome. The recognition of this fact is opening up great opportunities in personalised medicine and I don't see why psychology and psychiatry should be any different in principle.

It's true that most species contain a great deal of genetic variation. The vast majority of this variation is due to the slow fixation of nearly neutral alleles by random genetic drift.

There are also many examples of detrimental and beneficial alleles segregating in our species. There's no obvious reason why some of those couldn't affect specific behaviors of the sort proposed by evolutionary psychologists.

However, you don't build up an entire field of study by just declaring something to be "possible" and then proceeding as if it were a proven fact. It's just as possible that there's no such thing as a combination of alleles determining a specific behavior.

There are many traits that have presumably been under selection - such as looks, atheletic ability, intelligence and hand-eye coordination - but are not universally found in all humans; we are not all beautiful, underwear-model Einsteins who could play professional sport if only we tried a little harder. I do not see why a complex behavioural trait should be any different.

I believe that things like intelligence and physical appearance have a significant genetic component. The alleles for those traits have not become fixed in the species. I conclude that they do not confer much of a selective advantage.

In the case of the specific behaviors postulated by evolutionary psychologists, there's a real question about whether the actual alleles exist. And even if they do there's a real question about whether the beneficial effects are sufficient to raise the frequency to near fixation.

Your examples serve to discredit the just-so stories of the evolutionary psychologists since, as you point out, even obvious traits such as intelligence and beauty don't show much of a selective advantage.

I get twitchy when someone starts writing off an entire discipline/field because it usually mean they have misunderstood it. (The only people I usually see doing it are Creationists.)

I understand why you get "twitchy." My experience also suggests that attacks on a whole field of study are usually misguided.

However, evolutionary psychology seems to be the exception to the rule. The field has been under constant attack from the outside for more than twenty years. During all that time evolutionary psychologists have been unable to mount an adequate defense. Instead, they continue to publish garbage that's even mocked by the IDiots.

I've been blogging about this for four years and not a single evolutionary psychology defender (including you) has been able to address the serious problems in the field.

That's very telling.

I am open to being shown otherwise but, to me, the only real problem here is the poor coverage and over-hyping of pretty preliminary findings by New Scientist. This is nothing new, in my experience. New Scientist is science entertainment more than science education.

There are two problems. The problems with science journalism have been widely discussed here and elsewhere.

There's also a problem with the way science is done in general but at least in my fields there are knowledgeable scientists who speak out against the worst abuses and try to correct them. You've got to be suspicious about a discipline where skepticism and self-criticism seems to be lacking.

"You can't have it both ways. Either there's a strong selective advantage and high penetrance leading to a selective sweep in our ancestors, or the selective advantage is not strong and/or the penetrance is weak and the alleles did not become fixed. You need a different just-so story to explain the second scenario.

If the alleles have not become fixed in the population then it should be possible to find men who don't have the wife-beating-under-special-circumstances allele. Do they have fewer offspring, on average, than the wife-beaters?"

There is no necessity for a "wife-beating-under-special-circumstances allele" and the allele(s) that influence "wife-beating-under-special-circumstances" need not become fixed - that's my whole point. I'm not trying to have it both ways.

*If* a trait is under partial genetic control, complete penetrance or not, it is potentially under selection. Fact. You do not need complete penetrance or strong selection. A weak advantage will do if the the population size is big enough for selection to "see" it. Fact. If it is even occasionally selected for, it will hang around in the population. As far as I can tell, you are the one who is claiming that (a) the selection has to be strong, and (b) the trait has to reach fixation. The authors make no such claim and nor do I see why they should.

"That's quite possible although most of the just-so stories imply fixation."

But do they need fixation? No. Be careful of throwing the baby out with the bathwater. Have you modelled the possible selective advantages, penetrance and population sizes (and dynamics) to demonstrate that it cannot be selected? I suspect not. You appear to assume they are wrong, they assume they are right. I don't know whether you are right or they are but there is no conceptual reason why they have to be wrong, as you appear to be implying. Your dismissal without evidence is just as unscientific of their alleged claims without evidence. (Or more: "Our co-evolutionary theory of intimate partner violence clearly offers just a preliminary roadmap and makes no pretense to completeness.")

Personally, I suspect that wife-beating has a genetic influence but that alleles of different loci that influence it are in our population for other reasons and wife-beating is a pleiotropic effect. But that is just a hunch too.

"By comparing the typical human and typical chimp genomes we've discovered more than a million examples of fixation."

Indeed. (Although this is comparing one consensus genome with another.) Fixation does happen, though - I expressed myself badly. What I mean is that the ultimate end product of selection is not necessarily fixation. There may well be balancing selection - especially in something like agression, for which their is presumably some optimum - and especially for multi-locus traits, as the selective pressure - and direction - on alleles of one locus will depend heavily on the frequency of alleles at the other loci. The goalposts for selection are constantly moving and so fixation is not necessarily the norm unless you make your points of comparison very distant in time. (Even humans and chimps share some polymorphisms, though, I believe.)

"There are also many examples of detrimental and beneficial alleles segregating in our species. There's no obvious reason why some of those couldn't affect specific behaviors of the sort proposed by evolutionary psychologists."

So, in principle, the field of evolutionary psychology is sound?

"However, you don't build up an entire field of study by just declaring something to be "possible" and then proceeding as if it were a proven fact. It's just as possible that there's no such thing as a combination of alleles determining a specific behavior."

It is. This is true of all evolutionary fields, which often start with a "just-so story" hypothesis. You have to propose a hypothesis and then test it. (Falsify it.) That's science. Evolutionary psychologists do not test the genetics directly but test the predictions of the model. That is also science. All we have are models at the end of the day. The authors of this particular paper do not even mention the underlying genetics because it is not important for their model. The only important thing is that the behaviour has a genetic influence and might therefore be influenced by selection. As far as I can tell, they then make predictions based on their model and look to see if studies support or contradict these predictions. If they support them, the model is possibly useful. This is no different in essence than using a crystal structure model of a protein - something in an unnatural state that might be totally biologically artificial but still useful for making and testing hypothesis.

"I believe that things like intelligence and physical appearance have a significant genetic component. The alleles for those traits have not become fixed in the species. I conclude that they do not confer much of a selective advantage."

This is the crux, perhaps. On what basis do you "conclude that they do not confer much of a selective advantage"? Have you modelled the possible underlying population genetics and shown it to be impossible? I don't think we have enough data. You appear to be basing this on a hunch and assuming that the result of the evol psych is nonsense on the same hunch. It's your hunch versus theirs, except they attempt to test their hunch by seeing if the predictions it makes are born out by other data.

"In the case of the specific behaviors postulated by evolutionary psychologists, there's a real question about whether the actual alleles exist. And even if they do there's a real question about whether the beneficial effects are sufficient to raise the frequency to near fixation."

Questions, yes. Answers? Since when did questions stop something being valid science. If we stopped every time our assumptions were questioned, we'd never start.

"Your examples serve to discredit the just-so stories of the evolutionary psychologists since, as you point out, even obvious traits such as intelligence and beauty don't show much of a selective advantage."

On what criteria? Fixation? If the target of selection is moving, or there is balancing selection based on allele frequencies, fixation will not be reached. It would appear that my examples just highlight misunderstandings of evolutionary dynamics at the population level.

I have no dog in this fight as I am not an evolutionary psychologist. As a molecular geneticist, however, I have a big problem with the reasons for which you appear to be dismissing evol psych out of hand in this post. (Sorry.)

"However, evolutionary psychology seems to be the exception to the rule. The field has been under constant attack from the outside for more than twenty years. During all that time evolutionary psychologists have been unable to mount an adequate defense. Instead, they continue to publish garbage that's even mocked by the IDiots.

I've been blogging about this for four years and not a single evolutionary psychology defender (including you) has been able to address the serious problems in the field."

I'll dig around some older posts when I have time, then. I'm certainly not a dyed-in-the-wool defender of evolutionary psychology and would be interesting to see what the serious problems are. Coming as a neutral, and arriving when I did, however, the problems are not obvious and your post comes across as a rant without actual evidence to support your position. Worse, the attack of the whole field just comes across as rude and a little bigoted.

I say this as a fan of the blog - I just thought you would like to know how it can appear to a neutral.

Interested in what evolutionary psychologists really think? I strongly encourage the author of this blog and it's readers to take just 3 minutes and read this: http://www.epjournal.net/blog/2011/10/boobies-blue-footed-and-otherwise/

Interested in what evolutionary psychologists really think? I strongly encourage the author of this blog and it's readers to take just 3 minutes and read this: http://www.epjournal.net/blog/2011/10/boobies-blue-footed-and-otherwise/

You will not regret it (unless you're not interested in truth).

I completely agree with anonymous. That posting by Robert Kurzban tells us a lot about how evolutionary psychologists think. It ain't pretty.

This has got to be the dumbest misunderstanding of evolutionary psychology I have ever read.

Of course women weren't selecting for abuse. That is idiotic and no serious evolutionary psychologist argues anything to that effect.

The argument is that jealousy and possessiveness are adaptive traits in that they guard against the possibility of cuckoldry. That is, men who never became jealous or possessive were more easily duped into raising the offspring of other men and had fewer offspring than those who did display such behaviors. Abuse is just an extreme and very unfortunate manifestation of this.

Gotta love how this criticism of EP cites some introductory remarks on the topic but doesn't cite what evolutionary psychologists have to say on the topic in specifics. Intellectual dishonesty at its best I'd say.

Wow... have you ever read about evolutionary psychology? Our genes don't just make us do stuff, we can control ourselves. If you make sure your woman does not cheat on you, you have higher chances of passing your genes. Women are in a lot of cultures perceived as a property. A property you buy from her father, a property you steal, rape and go to war for. Women are a ressourcer we fight for. Hitting a woman is not okay... but it is not something someone made up along the way.

My uneducated guess would be that bullying weaker people is part of our genetic heritage, since it is so common, but I suspect it is a trait which goes back to the common ancestors of all primates and probably much earlier. Extremes of bullying behavior might be aberrations, however, like psychoses.

The ideal way to answer such questions would be bottom-up, by determining how each allele works, in combinations with other alleles. This reductionist method though can be very difficult and not always practical, otherwise the only science we would study would be physics (and math).

Laurence A. Moran

Larry Moran is a Professor Emeritus in the Department of Biochemistry at the University of Toronto. You can contact him by looking up his email address on the University of Toronto website.

Sandwalk

The Sandwalk is the path behind the home of Charles Darwin where he used to walk every day, thinking about science. You can see the path in the woods in the upper left-hand corner of this image.

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Quotations

The old argument of design in nature, as given by Paley, which formerly seemed to me to be so conclusive, fails, now that the law of natural selection has been discovered. We can no longer argue that, for instance, the beautiful hinge of a bivalve shell must have been made by an intelligent being, like the hinge of a door by man. There seems to be no more design in the variability of organic beings and in the action of natural selection, than in the course which the wind blows.Charles Darwin (c1880)Although I am fully convinced of the truth of the views given in this volume, I by no means expect to convince experienced naturalists whose minds are stocked with a multitude of facts all viewed, during a long course of years, from a point of view directly opposite to mine. It is so easy to hide our ignorance under such expressions as "plan of creation," "unity of design," etc., and to think that we give an explanation when we only restate a fact. Any one whose disposition leads him to attach more weight to unexplained difficulties than to the explanation of a certain number of facts will certainly reject the theory.

Charles Darwin (1859)Science reveals where religion conceals. Where religion purports to explain, it actually resorts to tautology. To assert that "God did it" is no more than an admission of ignorance dressed deceitfully as an explanation...

Quotations

The world is not inhabited exclusively by fools, and when a subject arouses intense interest, as this one has, something other than semantics is usually at stake.
Stephen Jay Gould (1982)
I have championed contingency, and will continue to do so, because its large realm and legitimate claims have been so poorly attended by evolutionary scientists who cannot discern the beat of this different drummer while their brains and ears remain tuned to only the sounds of general theory.
Stephen Jay Gould (2002) p.1339
The essence of Darwinism lies in its claim that natural selection creates the fit. Variation is ubiquitous and random in direction. It supplies raw material only. Natural selection directs the course of evolutionary change.
Stephen Jay Gould (1977)
Rudyard Kipling asked how the leopard got its spots, the rhino its wrinkled skin. He called his answers "just-so stories." When evolutionists try to explain form and behavior, they also tell just-so stories—and the agent is natural selection. Virtuosity in invention replaces testability as the criterion for acceptance.
Stephen Jay Gould (1980)
Since 'change of gene frequencies in populations' is the 'official' definition of evolution, randomness has transgressed Darwin's border and asserted itself as an agent of evolutionary change.
Stephen Jay Gould (1983) p.335
The first commandment for all versions of NOMA might be summarized by stating: "Thou shalt not mix the magisteria by claiming that God directly ordains important events in the history of nature by special interference knowable only through revelation and not accessible to science." In common parlance, we refer to such special interference as "miracle"—operationally defined as a unique and temporary suspension of natural law to reorder the facts of nature by divine fiat.
Stephen Jay Gould (1999) p.84

Quotations

My own view is that conclusions about the evolution of human behavior should be based on research at least as rigorous as that used in studying nonhuman animals. And if you read the animal behavior journals, you'll see that this requirement sets the bar pretty high, so that many assertions about evolutionary psychology sink without a trace.

Jerry Coyne
Why Evolution Is TrueI once made the remark that two things disappeared in 1990: one was communism, the other was biochemistry and that only one of them should be allowed to come back.

Sydney Brenner
TIBS Dec. 2000
It is naïve to think that if a species' environment changes the species must adapt or else become extinct.... Just as a changed environment need not set in motion selection for new adaptations, new adaptations may evolve in an unchanging environment if new mutations arise that are superior to any pre-existing variations

Douglas Futuyma
One of the most frightening things in the Western world, and in this country in particular, is the number of people who believe in things that are scientifically false. If someone tells me that the earth is less than 10,000 years old, in my opinion he should see a psychiatrist.

Francis Crick
There will be no difficulty in computers being adapted to biology. There will be luddites. But they will be buried.

Sydney Brenner
An atheist before Darwin could have said, following Hume: 'I have no explanation for complex biological design. All I know is that God isn't a good explanation, so we must wait and hope that somebody comes up with a better one.' I can't help feeling that such a position, though logically sound, would have left one feeling pretty unsatisfied, and that although atheism might have been logically tenable before Darwin, Darwin made it possible to be an intellectually fulfilled atheist

Richard Dawkins
Another curious aspect of the theory of evolution is that everybody thinks he understand it. I mean philosophers, social scientists, and so on. While in fact very few people understand it, actually as it stands, even as it stood when Darwin expressed it, and even less as we now may be able to understand it in biology.

Jacques Monod
The false view of evolution as a process of global optimizing has been applied literally by engineers who, taken in by a mistaken metaphor, have attempted to find globally optimal solutions to design problems by writing programs that model evolution by natural selection.